diff --git a/Trigger/TrigAlgorithms/TrigEFMissingET/src/EFMissingETFromCellsMT.h b/Trigger/TrigAlgorithms/TrigEFMissingET/src/EFMissingETFromCellsMT.h
index 18089672c45f43aeab2af03016f48cee5cd823a3..e6e0ff42047f53f50720de83a94c6ca92bc6ac65 100644
--- a/Trigger/TrigAlgorithms/TrigEFMissingET/src/EFMissingETFromCellsMT.h
+++ b/Trigger/TrigAlgorithms/TrigEFMissingET/src/EFMissingETFromCellsMT.h
@@ -31,7 +31,7 @@ class EFMissingETFromCellsMT: public extends<AthAlgTool, IMissingETTool> {
 
   virtual ~EFMissingETFromCellsMT(){}
 
-  virtual StatusCode  initialize();
+  virtual StatusCode  initialize() override;
 
   virtual StatusCode update( xAOD::TrigMissingET *met,
 			     TrigEFMissingEtHelper *metHelper ) const override;